LHC luminosity upgrade project moving to next phase

New quadrupole magnets, which focus particle beams before collisions, are one of the key technologies for the High-Luminosity LHC (Image: CERN)

This week more than 230 scientists and engineers from around the world met at CERN to discuss the High-Luminosity LHC – a major upgrade to the Large Hadron Collider (LHC) that will increase its discovery potential from 2025.

After a four-year design study the project is now moving into its second phase, which will see the development of industrial prototypes for various parts of the accelerator.

Luminosity is a crucial indicator of accelerator performance. It is proportional to the number of particles colliding within a defined amount of time. Since discoveries in particle physics rely on statistics, the greater the number of collisions, the more chances physicists have to see a particle or process that they have not seen before.

The High-Luminosity LHC will increase the luminosity by a factor of 10, delivering 10 times more collisions than the LHC would do over the same period of time. It will therefore provide more accurate measurements of fundamental particles and enable physicists to observe rare processes that occur below the current sensitivity level of the LHC.

The increase in luminosity will mean that physicists can study new phenomena discovered by the LHC, such as the Higgs boson, in more detail. The High-Luminosity LHC will produce 15 million Higgs bosons per year compared to the 1.2 million in total created at the LHC between 2011 and 2012.

Upgrading the LHC is a challenging project that relies on several breakthrough technologies, which are currently under development. Some 1.2 km of the LHC will be replaced by these new technologies, which include cutting-edge 12 tesla superconducting quadrupole magnets, brand new superconducting radiofrequency cavities or electrical transfer lines, based on high temperature superconductors. The High-Luminosity LHC will use these pioneering technologies for the very first time, which will not only increase the discovery potential of the LHC but also act as proof-of-concept for future accelerators.

All these technologies have been explored since 2011 in the framework of the HiLumi LHC Design Study – partly financed by the European Commission’s FP7 programme. HiLumi LHC brought together a large number of laboratories from CERN’s member states, as well as from Russia, Japan and the US. American institutes participated in the project with the support of the US LHC Accelerator Research Program (LARP), funded by the US Department of Energy. Some 200 scientists from 20 countries collaborated on this first successful phase.